The present invention relates to fluid supply systems, a configuration device, methods of operating a fluid supply system, and a software program or product. The present invention further relates to a sample separation system, in particular in a high performance liquid chromatography application.
In liquid chromatography, a fluidic sample and an eluent (liquid mobile phase) may be pumped through conduits and a column in which separation of sample components takes place. The column may comprise a material which is capable of separating different components of the fluidic analyte. Such a packing material, so-called stationary phase or sorbent which may comprise silica gel, may be filled into a column tube which may be connected to other elements (like a control unit, containers including sample and/or buffers) by conduits. The composition of the mobile phase can be adjusted by composing the mobile phase from different fluidic components with variable contributions.
EP 1,174,179 discloses a mixing apparatus where a fluid is progressing from an inlet tubing to an outlet tubing. Every segment of the liquid is part by part transferred to the outlet channel via numerous restrictor channels. The distances between the restrictor channels determine a dispersion pattern for any segment of the flow, progressing from the inlet chamber in the form of a reservoir channel to the outlet. The nearer the outlet channels are placed one to another, the higher is the permeability to the outlet collector at the respective location. Delaying partial flows of the fluid with different flow delays and providing different flow volumes for the partial flows results in a predetermined flow distribution function thus determining a dispersion pattern.
U.S. Pat. No. 4,496,245 discloses a combined proportioning valve and mixer usable in a liquid chromatography system for mixing solvents in predetermined ratios, and includes a magnetically driven stirrer rotatably disposed in a central chamber. Plural inlet lines allow solvents to enter the chamber at spaced positions. The chamber also communicates with outlet lines and is provided with means for preventing air bubbles from being entrapped in the stirrer and blocking flow through the system. Selectively controlled valve members control the flow of solvents through the inlet lines so as to achieve the preselected ratio of solvent mixing.
U.S. Pat. No. 4,155,683 discloses a system for and a method of providing an eluent composed of two different kinds of liquids being mixed at a set concentration and further a time varying concentration or mixing ratio, comprising a step for transferring each of the two liquids by sucking under low-pulsation to on-off valves, a step for periodically controlling the operation of the on-off valves, a step for controlling the amount of each liquid supplied to the mixing region during each period of valve operation, a step for substantially sucking the eluent formed by the above steps in the mixing region for discharging or supplying the same under the same low-pulsation.
U.S. Pat. No. 6,116,869 discloses a pumping system which mixes liquids with a well-controlled proportioning and flow rate. The pumping system comprises a liquid mixing device placed upstream from a pump. The liquids are taken from vessels, cyclically introduced, in a determined proportion, in a mixing chamber through alternate opening of on-off solenoid valves. The system is controlled at the input by using a damping means such as bellows in antechambers in order to avoid the effects of velocity discontinuities at the time of the opening and of the closing of the valves. The delivery of pump is controlled at the input as well as at the discharge end. The system may be used for liquid chromatography plants.
WO 2010/030720 discloses a method of reducing liquid composition errors in a low-pressure mixing pump system. Packets representing the switching intervals of each component of the desired fluid mixture are provided to an intake of the mixing pump system. For each packet, a switching time associated with at least one of the components in the packet is modulated. Modulated switching times are based on time offsets that are specifically selected according to the undesirable frequency characteristic of an intake response of the mixing pump system. The average of the volumes contributed by the packets thus modulated is equal to a component volume that achieves a desired proportion of the component in the output flow of the mixing pump system. Modulated switching times enable the reduction or elimination of composition error in the output flow of the mixing pump system.
US 2005/0224403 discloses a chromatographic monitor which includes an array of flow cells with individual light sensors that are collectively an array of photodiodes. The output from the photodiodes are multiplexed. To prevent losing information, the photodiodes are each connected to a different one of a plurality of inputs to the multiplexer through a corresponding one of a plurality of circuits that stores energy during the time the one inlet is not connected through the multiplexer to the signal processing circuitry that forms a part of an absorbance monitor.
U.S. Pat. No. 4,475,821 discloses a mixing chamber for liquids, which are supplied to the mixing chamber in measured quantities one after the other alternating over a period of time, in particular for liquid chromatographs, which is divided by a fine-pored filter plate into two areas. The inlet pipe is connected to one area and the outlet pipe is connected to the other of these areas. The two areas each widen out in a conical shape from the opening of the connected pipe towards the filter plate. The filter plate preferably consists of a steel or glass frit with a pore size in the range of 2 to 50 μm.
US 2004/042340 discloses three metal plate materials, each having penetration holes, which are united together in this order as a set at such positions that penetration holes can penetrate through the three metal plate materials so as to form a mixing portion. A plurality of sets, each having the mixing portion are integrated together at such positions that all of the penetration holes can penetrate through the respective sets of plate materials. The mixing portions of the respective sets are connected in parallel to one another.
DE 10 2006 058 026 discloses that a high performance liquid chromatography (HPLC) unit has an eluent source for producing an eluent stream in an eluent line. An injection unit is connected to the eluent line and a pillared unit is connected to the injection unit. A detector is connected to the pillared unit. A mixing chamber and a particle filter in a common mixing chamber forming a mixing chamber unit is arranged and is connected to streaming directly and consecutively.
In conventional chromatography systems in which multiple fluids are combined to form a solvent composition, artifacts in the solvent composition may occur which have a negative impact on the chromatographic performance.